27 research outputs found

    Correlation between reflectivity and photoluminescent properties of porous silicon films

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    Porous silicon (PS) layers were formed on p-type, oriented, 1–5 Ω cm resistivity Cz silicon wafers by electrochemical etching in an HF:C2H5OH (1:2 by volume) electrolyte at room temperature at a constant current density 20 mA/cm2. The etching duration was varied to achieve PS layers of different morphologies and thicknesses. Both the photoluminescence (PL) and the total diffused reflectivity spectra of the PS layers were measured. It was found that for the PS layers grown for etching durations of less than 90 s the PL emission is insignificant and reflectivity is quite low. Such PS layers can be used as antireflection coatings (ARC) on solar cells. The PS layers formed for etching durations greater than 90 s show a significant PL emission in 500–800 nm range with peak lying in 630–660 nm wavelength range. When etching duration increases from 90 s to 8 min the PL intensity increases and the PL peak shows a blue shift. With further increase in etching duration the PL intensity decreases and PL peak shows a red shift. The reflectivity of the photoluminescent layers increases with etching duration showing a highest value for a sample grown for 8 min. Further increase in etching duration up to 20 min the reflectivity decreases and then increases. Striking observation is that both the PL emission intensity and reflectivity in the wavelength range of 550–800 nm are maximum for the PS layer grown for the etching duration of 8 min

    Energy Expenditure and Nutritional Status of Sailors During One Month of Extensive Physical Training

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    The present study was conducted to determine nutritional requirements during extensive physical training by sailors of Indian Navy. A total of 37 sailors who were undergoing physical trainers course at training establishment of Indian Navy participated in this study. Energy expenditure, energy intakes, nutrient status and body composition changes during one month of training were recorded. Mean energy expenditure was found to be 4035 ±733 kcal/day and an average intake of 4478 ±340 kcal/day with sufficient amount of micro and macronutrients. The level of vitamin and minerals in blood and their excretion were in the normal range. Body composition was also maintained with a marginal decrease in body fat content. Increase in grip strength of passive hand was observed (Basal: 41.5 ± 8.8 kg, after 1 month of training:  46.5 ± 6.1 kg). Results indicate adequate nutritional support from the diet and positive effects of the training on healt

    Consumer Behavior towards Ready-to-Eat (RTE) Market: A Study of MTR Foods

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    MTR Foods is a well-known brand in the world for its packaged foods especially ready-to-eat meals. The purpose of this study is to determine the factors affecting the purchase decision of India’s and Malaysia’s consumers against the ready-to-eat (RTE) market. Online research and survey were done to collect the results. The factors influencing the consumer behavior includes price, convenience, taste, and nutrition. Most of the respondents are willing to make recommendation about MTR Foods. MTR Foods can improve its brand awareness by making more advertisement as there is around 27.9% of the respondents do not recognize the brand. Additionally, MTR Foods may conduct research in different states and countries for the company’s future planning

    The use of plants in the traditional management of diabetes in Nigeria: Pharmacological and toxicological considerations

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    Ethnopharmacological relevance: The prevalence of diabetes is on a steady increase worldwide and it is now identified as one of the main threats to human health in the 21st century. In Nigeria, the use of herbal medicine alone or alongside prescription drugs for its management is quite common. We hereby carry out a review of medicinal plants traditionally used for diabetes management in Nigeria. Based on the available evidence on the speciesŚł pharmacology and safety, we highlight ways in which their therapeutic potential can be properly harnessed for possible integration into the countryŚłs healthcare system. Materials and methods: Ethnobotanical information was obtained from a literature search of electronic databases such as Google Scholar, Pubmed and Scopus up to 2013 for publications on medicinal plants used in diabetes management, in which the place of use and/or sample collection was identified as Nigeria. ‘Diabetes’ and ‘Nigeria’ were used as keywords for the primary searches; and then ‘Plant name – accepted or synonyms’, ‘Constituents’, ‘Drug interaction’ and/or ‘Toxicity’ for the secondary searches. Results: The hypoglycemic effect of over a hundred out of the 115 plants reviewed in this paper is backed by preclinical experimental evidence, either in vivo or in vitro. One-third of the plants have been studied for their mechanism of action, while isolation of the bioactive constituent(s) has been accomplished for twenty three plants. Some plants showed specific organ toxicity, mostly nephrotoxic or hepatotoxic, with direct effects on the levels of some liver function enzymes. Twenty eight plants have been identified as in vitro modulators of P-glycoprotein and/or one or more of the cytochrome P450 enzymes, while eleven plants altered the levels of phase 2 metabolic enzymes, chiefly glutathione, with the potential to alter the pharmacokinetics of co-administered drugs. Conclusion: This review, therefore, provides a useful resource to enable a thorough assessment of the profile of plants used in diabetes management so as to ensure a more rational use. By anticipating potential toxicities or possible herb–drug interactions, significant risks which would otherwise represent a burden on the countryŚłs healthcare system can be avoided

    A model for homeopathic remedy effects: low dose nanoparticles, allostatic cross-adaptation, and time-dependent sensitization in a complex adaptive system

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    BACKGROUND: This paper proposes a novel model for homeopathic remedy action on living systems. Research indicates that homeopathic remedies (a) contain measurable source and silica nanoparticles heterogeneously dispersed in colloidal solution; (b) act by modulating biological function of the allostatic stress response network (c) evoke biphasic actions on living systems via organism-dependent adaptive and endogenously amplified effects; (d) improve systemic resilience. DISCUSSION: The proposed active components of homeopathic remedies are nanoparticles of source substance in water-based colloidal solution, not bulk-form drugs. Nanoparticles have unique biological and physico-chemical properties, including increased catalytic reactivity, protein and DNA adsorption, bioavailability, dose-sparing, electromagnetic, and quantum effects different from bulk-form materials. Trituration and/or liquid succussions during classical remedy preparation create “top-down” nanostructures. Plants can biosynthesize remedy-templated silica nanostructures. Nanoparticles stimulate hormesis, a beneficial low-dose adaptive response. Homeopathic remedies prescribed in low doses spaced intermittently over time act as biological signals that stimulate the organism’s allostatic biological stress response network, evoking nonlinear modulatory, self-organizing change. Potential mechanisms include time-dependent sensitization (TDS), a type of adaptive plasticity/metaplasticity involving progressive amplification of host responses, which reverse direction and oscillate at physiological limits. To mobilize hormesis and TDS, the remedy must be appraised as a salient, but low level, novel threat, stressor, or homeostatic disruption for the whole organism. Silica nanoparticles adsorb remedy source and amplify effects. Properly-timed remedy dosing elicits disease-primed compensatory reversal in direction of maladaptive dynamics of the allostatic network, thus promoting resilience and recovery from disease. SUMMARY: Homeopathic remedies are proposed as source nanoparticles that mobilize hormesis and time-dependent sensitization via non-pharmacological effects on specific biological adaptive and amplification mechanisms. The nanoparticle nature of remedies would distinguish them from conventional bulk drugs in structure, morphology, and functional properties. Outcomes would depend upon the ability of the organism to respond to the remedy as a novel stressor or heterotypic biological threat, initiating reversals of cumulative, cross-adapted biological maladaptations underlying disease in the allostatic stress response network. Systemic resilience would improve. This model provides a foundation for theory-driven research on the role of nanomaterials in living systems, mechanisms of homeopathic remedy actions and translational uses in nanomedicine

    Application of ZnO nanoparticles to enhance photoluminescence in porous silicon and its possible utilization for improving the short wavelength quantum efficiency of silicon solar cell

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    We have formed photoluminescent porous silicon (PS) layers and over which a ZnO layer (hereafter called ZnOPS layers) is deposited. We studied the photoluminescent properties of individual layers as well as the composite layer under excitation with 405 nm wavelength. Using the data of PL a theoretical analysis of a solar cell having such a composite layer of a given photoluminescent conversion efficiency eta(PL) on the front surface has been done. The condition of a photoluminescent composite layer (ZnOPS) useful for enhancing the spectral response of n(+)-p-p(+) structured silicon solar cell has been identified
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